Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, 222 South Tianshui Road, Lanzhou, 730000, Gansu, People's Republic of China.
Nanoscale Res Lett. 2009 May 15;4(8):814-9. doi: 10.1007/s11671-009-9320-z.
Well-crystallizedβ-SiC nanorods grown on electrospun nanofibers were synthesized by carbothermal reduction of Tb doped SiO2(SiO2:Tb) nanofibers at 1,250 °C. The as-synthesized SiC nanorods were 100-300 nm in diameter and 2-3 μm in length. Scanning electron microscopy (SEM) results suggested that the growth of the SiC nanorods should be governed by vapor-liquid-solid (VLS) mechanism with Tb metal as catalyst. Tb(NO3)3particles on the surface of the electrospun nanofibers were decomposed at 500 °C and later reduced to the formation of Tb nanoclusters at 1,200 °C, and finally the formation of a Si-C-Tb ally droplet will stimulate the VLS growth at 1,250 °C. Microstructure of the nanorod was further investigated by transmission electron microscopy (TEM). It was found that SiC <111> is the preferred initial growth direction. The liquid droplet was identified to be Si86Tb14, which acted as effective catalyst. Strong green emissions were observed from the SiC nanorod samples. Four characteristic photoluminescence (PL) peaks of Tb ions were also identified.
通过在 1250°C 下对 Tb 掺杂的 SiO2(SiO2:Tb)纳米纤维进行碳热还原,合成了在电纺纳米纤维上生长的结晶良好的β-SiC 纳米棒。合成的 SiC 纳米棒的直径为 100-300nm,长度为 2-3μm。扫描电子显微镜(SEM)结果表明,SiC 纳米棒的生长应遵循蒸气-液体-固(VLS)机制,其中 Tb 金属作为催化剂。电纺纳米纤维表面的 Tb(NO3)3 颗粒在 500°C 下分解,随后在 1200°C 下还原为 Tb 纳米簇的形成,最后 Si-C-Tb 共晶液滴的形成将刺激 1250°C 下的 VLS 生长。通过透射电子显微镜(TEM)进一步研究了纳米棒的微观结构。发现 SiC<111>是优先的初始生长方向。液滴被鉴定为 Si86Tb14,它充当了有效的催化剂。从 SiC 纳米棒样品中观察到强烈的绿色发射。还鉴定了 Tb 离子的四个特征光致发光(PL)峰。